Front bindings for cross-country skis are already known which comprise a locking slide movable longitudinally in a slide-track attached to the ski when acted upon by a control lever jointed to the binding shell. The slide comprises, at its front end, a transversely-positioned hook which is unitary with a core extending it rearward and which extends horizontally above a footing fastened to the upper surface of the ski. This core slides in a longitudinal track attached to the upper surface of the ski. Furthermore, the binding comprises a transversely-positioned frontal stop which is located behind the binding shell. This stop extends opposite the hook of the locking slide with which it cooperates to hold in the locked position, between itself and the hook of the slide, a transverse coupling pin fitted on the front portion of the sole of the boot. In the unlocked position, the locking slide is in a position such that the hook of the slide is moved away from the frontal stop. The front of the boot may then be coupled to the binding by inserting the transverse pin unitary with the front end of the sole in the space between the hook and the frontal stop, this pin insertion occurring in a downward direction toward the upper surface of the ski. Then, to lock the bonding, it is necessary only to maneuver the control lever of the binding so as to displace the locking slide and its hook until the latter is brought into the immediate proximity of the frontal stop. At that moment, the hook clamps the coupling pin of the boot and holds it immobile between itself and the frontal stop. This type of binding has the disadvantage of requiring that, to use it, the control lever of the binding must be operated manually.
Moreover, it is known that bindings are generally rendered unitary with the ski by means of screws penetrating through the base of this binding, thereby requiring that holes be provided in the part of the body of the binding which covers these screws, in order to allow access with a screwdriver. To prevent water from seeping into the inside of the ski at the screw positions and causing the ski to rot, or even to burst apart under the action of ice, screw covers must be provided. Now, these screw covers constitute a difficulty, first, from an aesthetic standpoint and second, as regards the additional manipulation required for their installation during the mounting operation. Furthermore, these screw covers may be lost during skiing, thus leading to the aforementioned problems.